skill. This selection was also based on the assumption that at this level they had, been exposed to a variety of genres of texts, and other theories in writing skill such as how
to organize paragraph and how to compose an argumentative writing. The researcher chose 30 essays from four classes as the subject of the
research. They are given some topics they have to compose, such as Public Transportation, Abortion, Smoking, and Entrepreneurship.
D. Population and Sample
According to Brown 1988:8, a population is any group of individuals that one or more characteristics in common are interesting to the researcher. The
population in statistics includes all members of a defined group that we are studying or collecting information. The population of this research is the fourth semester
students of IKIP PGRI Semarang with the total number of 120 students. The main reason for choosing this group of students was that in this semester the students
already got enough material of writing including the genre of paragraph writing and the theory of cohesion devices in writing. From these 120 students, all of them wrote
argumentative writing. However, only 30 texts were taken by the researcher as the data of the research.
In conducting the research, it will be difficult for the researcher if the data has large amount, therefore it is important to take sample from the population. Sample is
part of the population. According to Arikunto 1993:107 sample is a part of
population which is intended to be investigated. In this research the subjects being investigated are 30 students as the samples from the population.
The sampling technique used in this research is random sampling technique. Random sampling includes choosing subjects from a population through
unpredictable means. In its simplest form, all subjects have an equal chance of being selected out of the population being researched. According to Sumanto 1990: 23
random sampling is a process of choosing sample so that all individuals in a population have the same chance and the same opportunity to be chosen for the
sample. Therefore, in this research, the researcher chose 30 samples from 120 population randomly without looking any specific criteria for every samples which
are in the form of text. Random sampling was done by these following steps:
1. List all the names of the students in population. It consists of 120 students.
2. Write the names in a little piece of paper and rolled the paper
3. Pick 30 roll of papers which contain students’ names randomly as the data
of the research.
E. Data Collection
